chase



v Oct. 20, 1931.

G. C. CHASE CALCULATING MACHINE Filed March 15, 1929 2 Sheets-Sheet l Unverdor limo 6 614mm. 67 (P211 Cwmmflk GHQ/KEV A Oct. 20, 1931. G. c. CHASE I I CALCULATING MACHINE Filed March '15, 1929 2 Sheets-Sheet I 2 Pat ented Oct. go, 1931 UNITED STATES PATENT OFFICE GEORGE C. CHASE, OF sOUTH ORAN GE, NEW JERSEY, ASSIGNOR I'O MONROE CALCULAT- ING MACHDV E COMPAN Y, OF ORANGE, NEW JERSEY, A CORPORATION OF DELAWARE CALCULATING MACHINE Application filed March 13, 1929. Serial No. 346,686.

The invention relates to calculating machines, and more particularly to mechanism for facilitating the automatic calculation of problems in multiplication and in division.

' 5 According to the invention, means are provided for starting an additive registration on the numeral wheels of the machine and for thereafter automatically controlling. the stopping and/or carriage shifting and reversing devices, to determine the extent of the registration, by an over-carry action in the numeral wheels. V The invention consists in the novel construction and combination of parts, as set forth in the appended claims. The invention forms a modification of the mechanism of the known Monroe calculating machine, disclosed in essential particulars in applicants United States Patent Number 1,566,650, issued December 22, 1925, and in co-pending applications Number79,811 filed January 7, 1926, entitled Automatic control for calculating machines and Number 213,637, filed August 17, 1927, entitled Division stop mechanism for calculators, in combination with other devices disclosed in the co-pending application of E. F. Britten, Jr., Number 337,073,- filed February 2, 1929, and entitled Registering mechanism.

In these machines division may be accomplished by use of automatic control devices by either of the following methods The dividend being registered as a positive quantity in the numeral wheels, and the divisor being set in the keyboard, the automatic control lever is thrown into operative position, whereupon the actuatingv mechanism of the machine is set in operation by connection with an electric motor, the direction of rotation of the actuators being such as to cause subtractive registration upon the numeral wheels. Counting wheels are provided for registering the number of rotations of the actuators, this registration indicating the quotient at the end of the opera-' tion. \Vhen a subtractive registration has been continued until one more subtraction has been made than indicated by the correct quotient figure, the actuating mechanism is auto matically reversed and one corrective additive rotation is made, whereupon the carriage in which the numeral wheels are. mounted is shifted one decimal order toward the left and the operation is automatically repeated to determine the next quotient figure.

Division may also be accomplished by the following modification of this method; the counting wheels being provided with tens carry mechanism, according, for instance, to the disclosure of application Number 337,073

The dividend is registered in the numeral wheels as a negative quantity, that is to say, the complementof the dividend is registered, for which purpose the dividend is set up as a positive amount on the keyboard and registered negatively by operation of the subtract key. The divisor being new set in the keyboard, the add key is held depressed until the machine has registered the required or one more than the required quotient figure, whereupon the actuating mechanism will be automatically brought to rest. The numeral wheel carriage is now shifted one decimal order to the left and the automatic control lever is thrown into operative position, whereupon the subtractive rotation of the actuators will first make any necessary correction of the first quotient figure, and thereafter the machine will complete the division problem in the manner above described,

The principle Of-OPGIZLblOIl of this last de tiplier registered in the nunieral wheels aligned with the left-hand portion of the keyboard and the numeral 1 is set in the extreme left-hand column of the keyboard to represent a divisor, the multiplicand being set up at the right-hand portion of the keyboard. Upon operation by the add key and control lever, as described for the second method of division, the multiplier will be divided by one and the correct produpt will be registered in the numeral wheels aligning with the right-hand portion of the keyboard. In other words, according to this method, the

multiplier is first subtracted from zero and thereafter added back, a unit at a time, Whereby the multiplier value is enabled to control the number of rotations of the actuators.

By use of the present invention, the above described method of performing multiplication may be performed without necessitating the use of two motor keys to register the product in accordance with the first lefthand and of the lower order figures of the multiplier. It will also be apparent that, while multiplication has been simplified, division may still be performed without any additional operation, by means of the second method above described. 7.

In the accompanying drawings, illustrating the invention, Fig. 1 is a fragmentary left side elevation showing a multiplication and division control lever, with the associated parts of the control mechanism. Fig. 2 is a similar view showing the transmission, carriage shifting and other cooperating devices.

Fig. 3 is a fragmentary front elevation of the carriage shifting devices.

In these drawings, illustrating the invention as applied to the structure of the here inbefore named disclosures, the control lever is shown as made in two parts, the main portion 201 and a handle portion 318, mounted on a common fulcrum 202 of the framing and connected by a pin and slot means 300. The reversing clutch lever 111 carries at the forward end thereof a pawl 319, pivoted at 205 I and having a suitable. spring, acting to hold 1,566,650 hereinbeforereferred to, and, since the specific details of this mechanism form no part of the present invention, they are not illustrated herein. Control lever 201 also acts, through a bar 217 to engage a clutch hub 61 in the carriage shifting train with a clutch member on the shifting shaft 46.

The machine having been put in operation, will continue to run in'an additive direction until a transitional carry occurs, under the conditions described in the patent above named, at which time the full-cycle stop mechanism, illustrated in said patent, will operate to bring reversing clutch lever 111 into neutral position. Briefly, this action occurs through the operation of a pin of numeral Wheel 13, trigger 31, the falling of element of arm 24 into the path of rock 7 arm 22, and the action of pin 145 of arm 24 upon a cam face of lever 111.

212 of control lever 201, the movement of said lever to operating position'acting to move tooth 209 forwardly, against the tension of spring 210. Upon the side of reversing clutch lever 111 opposite tooth 209 is provided a pawl 213, the free end of which is adapted to fall behind a pin 211 and latch tooth 209 in forward position when so moved by the control lever.

The rebound of the mechanism referred to will cause tooth 220 of the link 21 of the stop mechanism to sweep upward and engage the forward end of the projecting tooth 209 and move the reversing clutch lever into subtractive position. Similarly, upon the operation of the transitional carry at the endof a subtractive rotation, arm 20 passing through its normal dead-center position on the rebound, tooth 220 of link-21 will sweep downward, engaging tooth 209 and moving the reversing clutch lever into additive position. These reversal operations, together with the automatic shifting of the numeral wheel carriage, thru the lever train 47, 52, 54, 55, cam with its clutch hub 61, shaft 46 and crank pin 64, fully described in the before named applications, will continue automatically until the carriage has reached its extreme left-hand position or until the lever 201 is manually returnedto inoperative position, whereupon the final quotient figure will be correctly registered and the machine automatically brought to rest.

It will be apparent that the machine will stop after the correct multiplier is registered even though no carriage movement occurs,

as when the operation is started with the carriage in extreme left-hand position or in case the operation is started by a forward and retractive movement of the control lever. This will be true whether there are one or more figures in the multiplier, as long as the numeral 1 set up in the keyboard is placed in alignment with the left-hand figure of the negatively registered multiplier. In the case of a multiplier of more than one figure, this last named method of operation will require the full number of rotations of the actuators called for by such multiplier (twelve rotations to multipl by twelve, etc.), since there is no shifting o the carriage to equal a multiplication by ten.

The above' method of operation would be useful in machines not equipped with shift- I able numeral wheel carriages. and in machines wherein certain operations must be performed without shifting the carriage; This latter condition is encountered in the machine disclosed in my United States Patent 1,468,992, issued September 25, 1923, and entitled Calculating machine, wherein British currency or other fractional problems are solved in a fixed position of the carriage. The application of the present invention to the machine constructed in accordance with this patent would enable multiplication to be performed in an automatic manner where one of the factors includes fractional values or values different portions of which have different denominators.

I claim: K 1. In a power driven calculating machine, having a product-dividend register comprising reversible numeral wheels, and actuators therefor operation control means including a member manually settable to determine rotation of said numeral wheels in an additive .direction and to initiate operation of the actuators, and means controlled by the settable means and by the numeral wheels and adopted to automatically reverse the direction of rotation of said wheels. I 2. In a power driven calculating machine having a transversely shiftable carriage, a product-dividend register comprising reversible numeral wheelsmounted in said carriage, and actuators therefor; operation control means including a member manually settable to determine rotation of said numeral wheels in an additive direction and to initiate operation of the actuators, and hieans controlled by the settable means andby the numeral 40 wheels and adapted to shift the numeral wheel carriageand to automatically reverse the direction of rotation of-said' wheels. In testimony whereof I afii; my si nature.

- GEO GE-C.C SE," 4 i 

